I have a 2004 Nissan Altima 2.5L with 160k miles. It's a project car I bought from a friend and I've done a few things on it. It currently has the above codes but it starts fine, idles smoothly and accelerates beautifully. For the P0303 (misfire) I noticed the valve cover gasket was leaking oil into the cylinders. I replaced the valve cover and gasket and replaced the spark plugs and swapped the #3 coil with #1 but the P0303 code came back. For the P1444 I replaced the Evap Purge Valve. Also replaced the gas cap and diagnosed and fixed some exhaust leaks. The gas tank seems to fill slowly and after filling it recently the P1444 code comes right back after clearing. And the Evap system monitor won't reset. Any ideas? Thanks
Maybe there's a leak somewhere in the EVAP system, or the canister is clogged.
Search Scotty's Youtube channel for "EVAP"
https://www.youtube.com/watch?v=PnU-SY6egr4
I checked for evap leaks. I'm leaning toward evap canister given the symptoms I noted.
Are you referring to the canister purge valve solenoid that you replaced?
yes